cli: ensure the program returns 0 on success and 1 on error

propagate a returncode in each operation and make it the
returncode of the program.

Prevent sys.exit calls in post(), get() and delete() request
handlers to enable cleanup code and error handling. Keep a basic
error log inside the request functions if the connection can't
be established or if the response contains an error code.

15 files changed, 237 insertions, 124 deletions

diff --git a/cli/objects/center.py b/cli/objects/center.py
index 80e5e3e..9948254 100644
--- a/cli/objects/center.py
+++ b/cli/objects/center.py
@@ -23,7 +23,10 @@ class OgCenter():
         payload = {'name': parsed_args.name}
         if parsed_args.desc:
             payload['comment'] = parsed_args.desc
-        rest.post('/center/add', payload=payload)
+        res = rest.post('/center/add', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def update_center(rest, args):
@@ -48,7 +51,10 @@ class OgCenter():
         }
         if parsed_args.comment:
             payload['comment'] = parsed_args.comment
-        rest.post('/center/update', payload=payload)
+        res = rest.post('/center/update', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def delete_center(rest, args):
@@ -60,4 +66,7 @@ class OgCenter():
                             help='center id in database')
         parsed_args = parser.parse_args(args)
         payload = {'id': parsed_args.id}
-        rest.post('/center/delete', payload=payload)
+        res = rest.post('/center/delete', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/client.py b/cli/objects/client.py
index cf5e0b9..a2f8356 100644
--- a/cli/objects/client.py
+++ b/cli/objects/client.py
@@ -14,8 +14,11 @@ class OgClient():
 
     @staticmethod
     def list_clients(rest):
-        r = rest.get('/clients')
-        print_json(r.text)
+        res = rest.get('/clients')
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def list_client_hardware(rest, args):
@@ -28,8 +31,11 @@ class OgClient():
         parsed_args = parser.parse_args(args)
 
         payload = {'client': parsed_args.client_ip}
-        r = rest.get('/hardware', payload=payload)
-        print_json(r.text)
+        res = rest.get('/hardware', payload=payload)
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def get_client_properties(rest, args):
@@ -41,8 +47,11 @@ class OgClient():
         parsed_args = parser.parse_args(args)
 
         payload = {'client': parsed_args.client_ip}
-        r = rest.get('/client/info', payload=payload)
-        print_json(r.text)
+        res = rest.get('/client/info', payload=payload)
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def request_refresh(rest, args):
@@ -55,7 +64,10 @@ class OgClient():
         parsed_args = parser.parse_args(args)
 
         payload = {'clients': parsed_args.client_ip}
-        rest.post('/refresh', payload=payload)
+        res = rest.post('/refresh', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def add_client(rest, args):
@@ -82,8 +94,8 @@ class OgClient():
                     nargs='?',
                     required=True,
                     help='specify the ip address of the client')
-        r = rest.get('/mode')
-        boot_choices = r.json()['modes']
+        res = rest.get('/mode')
+        boot_choices = res.json()['modes']
         parser.add_argument('--boot-mode',
                     nargs='?',
                     required=True,
@@ -100,7 +112,7 @@ class OgClient():
             err = True
         if err:
             parser.print_help(file=sys.stderr)
-            sys.exit(1)
+            return 1
         payload = {
             'name': parsed_args.hostname,
             'netmask': '0',
@@ -113,7 +125,10 @@ class OgClient():
             'netdriver': 'generic',
             'livedir': 'ogLive'
         }
-        rest.post('/client/add', payload=payload)
+        res = rest.post('/client/add', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def delete_client(rest, args):
@@ -127,4 +142,7 @@ class OgClient():
         payload = {
             'clients': parsed_args.ip,
         }
-        rest.post('/client/delete', payload=payload)
+        res = rest.post('/client/delete', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/disks.py b/cli/objects/disks.py
index e00b760..81b404e 100644
--- a/cli/objects/disks.py
+++ b/cli/objects/disks.py
@@ -23,8 +23,11 @@ class OgDisk():
         parsed_args = parser.parse_args(args)
         payload = {'client': [parsed_args.client_ip]}
 
-        r = rest.get('/client/setup', payload=payload)
-        print_json(r.text)
+        res = rest.get('/client/setup', payload=payload)
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def setup_disk(rest, args):
@@ -79,8 +82,8 @@ class OgDisk():
                            help='Specific client IP')
 
         parsed_args = parser.parse_args(args)
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -93,11 +96,11 @@ class OgDisk():
             ips.add(l)
         if not ips:
             print("Missing --client-ip, or --room-id/--center-id. No clients provided.")
-            return None
+            return 1
 
         if not parsed_args.num.isdigit():
             print(f'Invalid disk number: must be an integer value')
-            return
+            return 1
 
         payload = {'clients': parsed_args.client_ip, 'type': disk_type_map[parsed_args.type], 'disk': str(parsed_args.num),
                    'cache': '0', 'cache_size': '0', 'partition_setup': []}
@@ -109,31 +112,31 @@ class OgDisk():
 
             if len(p) != 4:
                 print(f'Invalid partition: requires "num,part_scheme,fs,size", "{",".join(p)}" provided')
-                return
+                return 1
             part_num, code, fs, size = p[0], p[1].upper(), p[2].upper(), p[3]
 
             if not part_num.isdigit():
                 print(f'Invalid partition: the first parameter must be a number, "{part_num}" provided')
-                return
+                return 1
 
             if part_num in defined_part_indices:
                 print(f'Invalid partition: partition number "{part_num}" has multiple definitions')
-                return
+                return 1
 
             defined_part_indices.add(part_num)
 
             if code not in part_types:
                 print(f'Invalid partition {i}: specified partition type {code} is not supported. The supported formats are {part_types}')
-                return
+                return 1
 
             if fs not in fs_types:
                 print(f'Invalid partition {i}: specified filesystem {fs} is not supported. The supported formats are {fs_types}')
-                return
+                return 1
             try:
                 size = parse_size(size)
             except ValueError as error:
                 print(f'Invalid partition {i}: {str(error)}')
-                return
+                return 1
 
             for j in range(i, int(part_num)):
                 part = {'partition': str(j), 'code': 'EMPTY',
@@ -158,4 +161,7 @@ class OgDisk():
                     'format': '0'}
             payload['partition_setup'].append(part)
 
-        rest.post('/setup', payload=payload)
+        res = rest.post('/setup', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/folder.py b/cli/objects/folder.py
index c4da900..2519446 100644
--- a/cli/objects/folder.py
+++ b/cli/objects/folder.py
@@ -39,7 +39,10 @@ class OgFolder():
             payload['room'] = parsed_args.room_id
         if parsed_args.center_id:
             payload['center'] = parsed_args.center_id
-        rest.post('/folder/add', payload=payload)
+        res = restest.post('/folder/add', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def update_folder(rest, args):
@@ -58,7 +61,10 @@ class OgFolder():
             'id': parsed_args.id,
             'name': parsed_args.name,
         }
-        rest.post('/folder/update', payload=payload)
+        res = rest.post('/folder/update', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def delete_folder(rest, args):
@@ -70,4 +76,7 @@ class OgFolder():
                             help='folder id in database')
         parsed_args = parser.parse_args(args)
         payload = {'id': parsed_args.id}
-        rest.post('/folder/delete', payload=payload)
+        res = rest.post('/folder/delete', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/images.py b/cli/objects/images.py
index e6e61d0..10f6fd5 100644
--- a/cli/objects/images.py
+++ b/cli/objects/images.py
@@ -21,10 +21,10 @@ def get_repository(repository_id, rest):
 
 
 def get_repositories(rest):
-    r = rest.get('/repositories')
-    if not r or r.status_code != requests.codes.ok:
+    res = rest.get('/repositories')
+    if not res:
         return None
-    repositories = r.json()['repositories']
+    repositories = res.json()['repositories']
     return repositories
 
 
@@ -32,8 +32,11 @@ class OgImage():
 
     @staticmethod
     def list_images(rest):
-        r = rest.get('/images')
-        print_json(r.text)
+        res = rest.get('/images')
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def restore_image(rest, args):
@@ -78,8 +81,8 @@ class OgImage():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -93,34 +96,37 @@ class OgImage():
 
         if not ips:
             print('Missing --client-ip, or --room-id/--center-id. No clients provided.')
-            return
+            return 1
 
-        r = rest.get('/images')
-        images = r.json()
+        res = rest.get('/images')
+        images = res.json()
         found_image = [img for img in images['images']
                        if img['id'] == parsed_args.id]
         if not found_image:
             print(f'Image with id {parsed_args.id} not found.')
-            return
+            return 1
         else:
             found_image = found_image[0]
 
         selected_repo_id = 0
         for ip in parsed_args.client_ip:
-            r = rest.get('/client/info', payload={'client': ip})
-            repo_id = r.json()['repo_id']
+            res = rest.get('/client/info', payload={'client': ip})
+            repo_id = res.json()['repo_id']
             if selected_repo_id == 0:
                 selected_repo_id = repo_id
             elif selected_repo_id != repo_id:
                 print(f'cannot restore clients assigned to different repositories')
-                return
+                return 1
 
         payload = {'disk': parsed_args.disk, 'partition': parsed_args.part,
                    'id': str(parsed_args.id), 'name': found_image['name'],
                    'profile': str(found_image['software_id']),
                    'repository_id': repo_id,
                    'type': parsed_args.type.upper(), 'clients': list(ips)}
-        r = rest.post('/image/restore', payload=payload)
+        res = rest.post('/image/restore', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def create_image(rest, args):
@@ -149,19 +155,19 @@ class OgImage():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/client/info', payload={'client': parsed_args.client_ip})
-        center_id = r.json()['center']
-        repo_id = r.json()['repo_id']
+        res = rest.get('/client/info', payload={'client': parsed_args.client_ip})
+        center_id = res.json()['center']
+        repo_id = res.json()['repo_id']
 
-        r = rest.get('/client/setup',
+        res = rest.get('/client/setup',
                      payload={'client': parsed_args.client_ip})
-        if r.status_code == 200:
+        if res.status_code == 200:
             part_info = list(filter(lambda x: x['disk'] == int(parsed_args.disk) and
                              x['partition'] == int(parsed_args.part),
-                             r.json()['partitions']))
+                             res.json()['partitions']))
             if not part_info:
                 print('Partition not found.')
-                return
+                return 1
             fs_code = list(part_info)[0]['code']
 
         image_name = remove_accents(parsed_args.name)
@@ -171,7 +177,10 @@ class OgImage():
         if parsed_args.desc:
             payload['description'] = parsed_args.desc
 
-        rest.post('/image/create', payload=payload)
+        res = rest.post('/image/create', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def update_image(rest, args):
@@ -202,32 +211,32 @@ class OgImage():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/client/info', payload={'client': parsed_args.client_ip})
-        center_id = r.json()['center']
-        repo_id = int(r.json()['repo_id'])
+        res = rest.get('/client/info', payload={'client': parsed_args.client_ip})
+        center_id = res.json()['center']
+        repo_id = int(res.json()['repo_id'])
 
-        r = rest.get('/client/setup',
+        res = rest.get('/client/setup',
                      payload={'client': parsed_args.client_ip})
-        if r.status_code == 200:
+        if res.status_code == 200:
             part_info = list(filter(lambda x: x['disk'] == int(parsed_args.disk) and
                              x['partition'] == int(parsed_args.part),
-                             r.json()['partitions']))
+                             res.json()['partitions']))
             if not part_info:
                 print('Partition not found.')
-                return
+                return 1
             fs_code = list(part_info)[0]['code']
 
-        r = rest.get('/images')
+        res = rest.get('/images')
         image_name = None
-        if r.status_code == 200:
-            for image in r.json()['images']:
+        if res.status_code == 200:
+            for image in res.json()['images']:
                 if image['id'] == int(parsed_args.id):
                     image_name = image['name']
                     break
 
         if not image_name:
             print('Image not found')
-            return
+            return 1
         else:
             print(f'Updating {image_name} image')
 
@@ -241,4 +250,7 @@ class OgImage():
                    'code': str(fs_code),
                    'name': image_name}
 
-        rest.post('/image/update', payload=payload)
+        res = rest.post('/image/update', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/live.py b/cli/objects/live.py
index c90a4c2..7a057bf 100644
--- a/cli/objects/live.py
+++ b/cli/objects/live.py
@@ -13,5 +13,8 @@ class OgLive():
 
     @staticmethod
     def list_live(rest):
-        r = rest.get('/oglive/list')
-        print_json(r.text)
+        res = rest.get('/oglive/list')
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
diff --git a/cli/objects/modes.py b/cli/objects/modes.py
index 7cf78e2..2374777 100644
--- a/cli/objects/modes.py
+++ b/cli/objects/modes.py
@@ -14,8 +14,11 @@ class OgModes():
 
     @staticmethod
     def list_available_modes(rest):
-        r = rest.get('/mode')
-        print_json(r.text)
+        res = rest.get('/mode')
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def set_modes(rest, args):
@@ -44,8 +47,8 @@ class OgModes():
                             help='Boot mode to be set')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -59,7 +62,10 @@ class OgModes():
 
         if not ips:
             print("Missing --client-ip, or --room-id/--center-id. No clients provided.")
-            return None
+            return 1
 
         payload = {'clients': list(ips), 'mode': parsed_args.mode[0]}
-        r = rest.post('/mode', payload=payload)
+        res = rest.post('/mode', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/poweroff.py b/cli/objects/poweroff.py
index af309bf..ab14b0d 100644
--- a/cli/objects/poweroff.py
+++ b/cli/objects/poweroff.py
@@ -36,8 +36,8 @@ class OgPoweroff():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -51,7 +51,10 @@ class OgPoweroff():
 
         if not ips:
             print("Missing --client-ip, or --room-id/--center-id. No clients provided.")
-            return None
+            return 1
 
         payload = {'clients': list(ips)}
-        r = rest.post('/poweroff', payload=payload)
+        res = rest.post('/poweroff', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/reboot.py b/cli/objects/reboot.py
index ca2ee9f..4f7f755 100644
--- a/cli/objects/reboot.py
+++ b/cli/objects/reboot.py
@@ -36,8 +36,8 @@ class OgReboot():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -51,7 +51,10 @@ class OgReboot():
 
         if not ips:
             print("Missing --client-ip, or --room-id/--center-id. No clients provided.")
-            return None
+            return 1
 
         payload = {'clients': list(ips)}
-        r = rest.post('/reboot', payload=payload)
+        res = rest.post('/reboot', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/repo.py b/cli/objects/repo.py
index 7085633..d172a0d 100644
--- a/cli/objects/repo.py
+++ b/cli/objects/repo.py
@@ -13,8 +13,11 @@ class OgRepo():
 
     @staticmethod
     def list_repos(rest):
-        r = rest.get('/repositories')
-        print_json(r.text)
+        res = rest.get('/repositories')
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def _add_repo(rest, parsed_args):
@@ -22,37 +25,43 @@ class OgRepo():
             'addr': parsed_args.ip,
             'name': parsed_args.name,
         }
-        rest.post('/repository/add', payload=payload)
+        res = rest.post('/repository/add', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def _add_repo_ip(rest, parsed_args):
         for ip in parsed_args.ip:
             if not check_address(ip):
                 print(f'Invalid IP address: {ip}')
-                return
+                return 1
 
-        r = rest.get('/repositories')
+        res = rest.get('/repositories')
         target_repo = None
-        for repo in r.json()['repositories']:
+        for repo in res.json()['repositories']:
             if repo['id'] == parsed_args.id:
                 target_repo = repo
                 break
 
         if not target_repo:
             print('Invalid repository id specified')
-            return
+            return 1
 
         for ip in parsed_args.ip:
             if ip in target_repo['addr']:
                 print(f'The repository already contains the address {ip}')
-                return
+                return 1
 
         payload = {
             'id': parsed_args.id,
             'addr': target_repo['addr'] + parsed_args.ip,
             'name': target_repo['name'],
         }
-        rest.post('/repository/update', payload=payload)
+        res = rest.post('/repository/update', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def add_repo(rest, args):
@@ -101,30 +110,33 @@ class OgRepo():
             'name': parsed_args.name,
         }
 
-        rest.post('/repository/update', payload=payload)
+        res = rest.post('/repository/update', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def _delete_repo_ip(rest, parsed_args):
         for ip in parsed_args.ip:
             if not check_address(ip):
                 print(f'Invalid IP address: {ip}')
-                return
+                return 1
 
-        r = rest.get('/repositories')
+        res = rest.get('/repositories')
         target_repo = None
-        for repo in r.json()['repositories']:
+        for repo in res.json()['repositories']:
             if repo['id'] == parsed_args.id:
                 target_repo = repo
                 break
 
         if not target_repo:
             print('Invalid repository id specified')
-            return
+            return 1
 
         for ip in parsed_args.ip:
             if ip not in target_repo['addr']:
                 print(f'Invalid address {ip}: The repository has the following IPs: {target_repo["addr"]}')
-                return
+                return 1
 
             target_repo['addr'].remove(ip)
 
@@ -133,12 +145,18 @@ class OgRepo():
             'addr': target_repo['addr'],
             'name': target_repo['name'],
         }
-        rest.post('/repository/update', payload=payload)
+        res = rest.post('/repository/update', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def _delete_repo(rest, parsed_args):
         payload = {'id': parsed_args.id}
-        rest.post('/repository/delete', payload=payload)
+        res = rest.post('/repository/delete', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def delete_repo(rest, args):
@@ -184,8 +202,8 @@ class OgRepo():
                            help='Any valid client ip address')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for room in parsed_args.room_id:
@@ -195,7 +213,10 @@ class OgRepo():
             ips.add(l)
         if not ips:
             print('No valid clients specified.')
-            return
+            return 1
 
         payload = {'id': parsed_args.id, 'clients': list(ips)}
-        rest.post('/client/repo', payload=payload)
+        res = rest.post('/client/repo', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/room.py b/cli/objects/room.py
index f22c843..da9a872 100644
--- a/cli/objects/room.py
+++ b/cli/objects/room.py
@@ -65,7 +65,7 @@ class OgRoom():
             err = True
         if err:
             parser.print_help(file=sys.stderr)
-            sys.exit(1)
+            return 1
 
         payload = {
             'name': parsed_args.name,
@@ -82,7 +82,10 @@ class OgRoom():
             payload['folder_id'] = parsed_args.folder
         if parsed_args.desc:
             payload['location'] = parsed_args.desc
-        rest.post('/room/add', payload=payload)
+        res = rest.post('/room/add', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def update_room(rest, args):
@@ -115,7 +118,7 @@ class OgRoom():
             err = True
         if err:
             parser.print_help(file=sys.stderr)
-            sys.exit(1)
+            return 1
 
         payload = {
             'id': parsed_args.id,
@@ -124,7 +127,10 @@ class OgRoom():
             'gateway': parsed_args.gateway,
         }
         
-        rest.post('/room/update', payload=payload)
+        res = rest.post('/room/update', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def delete_room(rest, args):
@@ -136,5 +142,8 @@ class OgRoom():
                             help='room id in database')
         parsed_args = parser.parse_args(args)
         payload = {'id': parsed_args.id}
-        rest.post('/room/delete', payload=payload)
+        res = rest.post('/room/delete', payload=payload)
+        if not res:
+            return 1
+        return 0
 
diff --git a/cli/objects/scopes.py b/cli/objects/scopes.py
index 548b93c..5779f78 100644
--- a/cli/objects/scopes.py
+++ b/cli/objects/scopes.py
@@ -57,7 +57,7 @@ class OgScope():
         for ip in parsed_args.client_ip:
             ips.add(ip)
 
-        r = rest.get('/scopes')
+        res = rest.get('/scopes')
         json_data = json.loads(r.text)
 
         if parsed_args.name:
@@ -71,8 +71,7 @@ class OgScope():
                 path = _get_client_path(json_data, client_ip, None)
                 for i, item in enumerate(path):
                     print('  ' * i + item)
-            return None
         else:
             print_json(r.text)
-            return None
+        return 0
 
diff --git a/cli/objects/server.py b/cli/objects/server.py
index 468ff00..26b2c50 100644
--- a/cli/objects/server.py
+++ b/cli/objects/server.py
@@ -13,8 +13,11 @@ class OgServer():
 
     @staticmethod
     def list_servers(rest):
-        r = rest.get('/server')
-        print_json(r.text)
+        res = rest.get('/server')
+        if not res:
+            return 1
+        print_json(res.text)
+        return 0
 
     @staticmethod
     def add_server(rest, args):
@@ -27,10 +30,13 @@ class OgServer():
 
         if not check_address(parsed_args.ip):
             print(f'Invalid IP address: {parsed_args.ip}')
-            return
+            return 1
 
         payload = {'address': parsed_args.ip}
-        rest.post('/server', payload=payload)
+        res = rest.post('/server', payload=payload)
+        if not res:
+            return 1
+        return 0
 
     @staticmethod
     def delete_server(rest, args):
@@ -42,4 +48,7 @@ class OgServer():
                             help='server id in the database')
         parsed_args = parser.parse_args(args)
         payload = {'id': parsed_args.id}
-        rest.delete('/server', payload=payload)
+        res = rest.delete('/server', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/session.py b/cli/objects/session.py
index 0168cb3..4fde4d0 100644
--- a/cli/objects/session.py
+++ b/cli/objects/session.py
@@ -44,8 +44,8 @@ class OgSession():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -59,11 +59,14 @@ class OgSession():
 
         if not ips:
             print("Missing --client-ip, or --room-id/--center-id. No clients provided.")
-            return None
+            return 1
 
         payload = {
             'clients': list(ips),
             'disk': parsed_args.disk,
             'partition': parsed_args.part,
         }
-        r = rest.post('/session', payload=payload)
+        res = rest.post('/session', payload=payload)
+        if not res:
+            return 1
+        return 0
diff --git a/cli/objects/wol.py b/cli/objects/wol.py
index 9eba702..7284895 100644
--- a/cli/objects/wol.py
+++ b/cli/objects/wol.py
@@ -53,8 +53,8 @@ class OgWol():
                            help='Specific client IP')
         parsed_args = parser.parse_args(args)
 
-        r = rest.get('/scopes')
-        scopes = r.json()
+        res = rest.get('/scopes')
+        scopes = res.json()
         ips = set()
 
         for center in parsed_args.center_id:
@@ -68,7 +68,10 @@ class OgWol():
 
         if not ips:
             print("Missing --client-ip, or --room-id/--center-id. No clients provided.")
-            return None
+            return 1
 
         payload = {'type': parsed_args.type, 'clients': list(ips)}
-        r = rest.post('/wol', payload=payload)
+        res = rest.post('/wol', payload=payload)
+        if not res:
+            return 1
+        return 0